Open Middle - Johnson, Nanette; and Kaplinsky, Robert
"Open middle" problems, hints, and answers, all aligned to the Common Core State Standards (CCSS). Introduced by Dan Meyer, these kinds of math challenges have a "closed beginning," meaning that they all start with the same initial problem; a "closed
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Optical Data School Media
A publisher of math and science programs, including Windows on Math, an activity-based laserdisc and videotape curriculum built around the NCTM standards. Most products are for levels K-8. Find Correlations for Optical Data products to a wide range of
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Orbifold Pinball - Yevgeniy Dodis; The Geometry Center
A game in which you roll a ball on an unusual playing field. The game board is like ordinary pinball in that it features 'bumpers' off which the ball can bounce. But in this game, the board is 'curved' in such a way that a ball barely missing the bumper
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Orbit Research
Developers and manufacturers of Orion Talking Scientific calculators the TI-84 Plus and the TI-36X, the iBill Talking Banknote Identifier, and other "products that enable an independent lifestyle for the physically challenged" -- the visually impaired
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ostermiller.org - Stephen Ostermiller
Converters, Calculators, and JavaScript include Multiplication Game, in which letters represent digits in a multiplication problem; Length, which converts between units of length and distance; Roman Numerals, which converts between Arabic and Roman numerals;
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Overthinking My Teaching - Christopher Danielson
Blog by a community college math teacher "interested in hard questions about teaching." Posts, which date back to July, 2009, have included "Wump hats," "An unnoticed rule for number language," "The end of word problems," "Cubeyness," "Cardinal and ordinal
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Oxford University Press
The world's largest university press, publishing 3,000 new books a year, including scholarly works in all academic disciplines, bibles, music, school and college textbooks, children's books, materials for teaching English as a second language, business
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P2S Games - P2S Information Systems Pvt. Ltd
Online games that challenge you to click your way to filling containers of liquids (Fill It Up), completing equations with operations (Equation), adding adjacent tiles to maximize their overall sum (Maximize), selecting operations between the 4s to make
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Palindromic Primes - Ivars Peterson (MathTrek)
Palindromic primes are whole numbers, evenly divisible only by themselves and 1, that also have the same sequence of digits read forward or backward... The current record for the largest known palindromic prime is held by Harvey Dubner, a retired electrical
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Panamath - Panamath.org
Have you ever tried to guess how many jelly beans are in a jar without counting? The Panamath test measures your number sense -- your intuitive recognition of numbers and their relationships -- and approximate number system (ANS) aptitude. Practice estimating
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paperfolding.com - Eric Andersen
Learn to fold origami from diagrams; read about the history of paper-folding, including the origin of the term "origami." The origami & math essay contains sections such as Origami, Geometry, and the Kawasaki Theorem; and Origami and Topology.
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Paper Mosaics - Alex Bateman
Origami tessellations consist of a simple crease pattern unit that gets repeated across a sheet of paper. Download Tess, a computer program that aids in the design of such tilings; and browse a gallery of works created with the application.
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Papers by Dr. Bert K. Waits - Dr. Bert K. Waits
In PDF format, essays include "The Role of Hand-Held Computer Symbolic Algebra in Mathematics Education in the Twenty-First Century: A Call for Action!"; "The Role of Graphing Calculators in Mathematics Reform"; "The Evolution of Instructional Use of
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Parent's Page - Chicago System Initiative (CSI)
A list of informative sites for parents who have questions about parenting and how to get involved in their children's education. Topics include Family Math (a page on math education); Helping your child learn math; Math and Your Child (information on
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